Page 1 of 1

Error in routine epw_setup (1): coarse k-mesh needs to be strictly positive in 1st BZ

Posted: Fri May 14, 2021 5:17 pm
by zega14
Dear All

I hope everyone is doing great. I was running el_phonon calculation for ibrav=4 using epw. However, the calculation crashed on the epw step with the error " Error in routine epw_setup (1): coarse k-mesh needs to be strictly positive in 1st BZ". I have generated a positive definite grid (6x6x4) between 0 and 1 for nscf calculation employing kmesh.pl. How could I solve this error? Thank you.


Sincerely, Zegnet

Re: Error in routine epw_setup (1): coarse k-mesh needs to be strictly positive in 1st BZ

Posted: Sun May 16, 2021 1:44 pm
by hpaudya1
Hi Zegnet,

Can you make sure that nscf.out has same number and list of k-points provided in nscf.in? Sometimes, QE prints different number and list of k-points because of the symmetry.

If this is the case, you can use calculations = 'bands' in nscf.in.

Hope this works.

Best,
Hari Paudyal

Re: Error in routine epw_setup (1): coarse k-mesh needs to be strictly positive in 1st BZ

Posted: Mon May 17, 2021 2:56 pm
by zega14
Dear Hari Paudyal

Thank you very much! Your suggestion works. Indeed, the number of k points were different in nscf.in and nscf.out. I have come up with a different error but I am trying to solve it before posting here.


Sincerely, Zegnet